ZoneCheck

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This is quick test to determin if a DNS server is an Open Resolver.

DNS servers must only ever answer queries for local IP ranges/subnets, and never for third parties.
The dangers in not doing so are many and serious, including DDoS attacks.


Enter a DNS Server Address (hostname or IP)
* Names default to IPv4
 

 

Copyright © Noel Butler 1994-2014. All Rights Reserved.